http://www.chonday.com/Videos/cruishalcut2
Check out this Video of a Norwegian cruise dry docks in a German ship yard and get's Cut in 1/2 and Stretched 99 Feet as a new section is Added. It's pretty amazing.
This way of doing things seems like they could Double the size of the ship in the same time it took them to add 99 feet. And I like the Idea of Refreshing the Boat instead of Scrapping and Rebuilding a new ship.